Files
elm-0.19-workshop/advanced/server/services/articles.service.js
2018-08-05 06:07:14 -04:00

614 lines
16 KiB
JavaScript

"use strict";
const { MoleculerClientError } = require("moleculer").Errors;
const { ForbiddenError } = require("moleculer-web").Errors;
const _ = require("lodash");
const slug = require("slug");
const DbService = require("../mixins/db.mixin");
module.exports = {
name: "articles",
mixins: [DbService("articles")],
/**
* Default settings
*/
settings: {
fields: ["_id", "title", "slug", "description", "body", "tagList", "createdAt", "updatedAt", "favorited", "favoritesCount", "author", "comments"],
// Populates
populates: {
author: {
action: "users.get",
params: {
fields: ["username", "bio", "image"]
}
},
comments: {
action: "comments.get",
params: {
fields: ["_id", "body", "author"],
populates: ["author"]
}
},
favorited(ids, articles, rule, ctx) {
if (ctx.meta.user)
return this.Promise.all(articles.map(article => ctx.call("favorites.has", { article: article._id.toString(), user: ctx.meta.user._id.toString() }).then(res => article.favorited = res)));
else {
articles.forEach(article => article.favorited = false);
return this.Promise.resolve();
}
},
favoritesCount(ids, articles, rule, ctx) {
return this.Promise.all(articles.map(article => ctx.call("favorites.count", { article: article._id.toString() }).then(count => article.favoritesCount = count)));
}
},
// Validation schema for new entities
entityValidator: {
title: { type: "string", min: 1 },
description: { type: "string", min: 1 },
body: { type: "string", min: 1 },
tagList: { type: "array", items: "string", optional: true },
}
},
/**
* Actions
*/
actions: {
/**
* Create a new article.
* Auth is required!
*
* @actions
* @param {Object} article - Article entity
*
* @returns {Object} Created entity
*/
create: {
auth: "required",
params: {
article: { type: "object" }
},
handler(ctx) {
let entity = ctx.params.article;
return this.validateEntity(entity)
.then(() => {
entity.slug = slug(entity.title, { lower: true }) + "-" + (Math.random() * Math.pow(36, 6) | 0).toString(36);
entity.author = ctx.meta.user._id.toString();
entity.createdAt = new Date();
entity.updatedAt = new Date();
return this.adapter.insert(entity)
.then(doc => this.transformDocuments(ctx, { populate: ["author", "favorited", "favoritesCount"]}, doc))
.then(entity => this.transformResult(ctx, entity, ctx.meta.user))
.then(json => this.entityChanged("created", json, ctx).then(() => json));
});
}
},
/**
* Update an article.
* Auth is required!
*
* @actions
* @param {String} id - Article ID
* @param {Object} article - Article modified fields
*
* @returns {Object} Updated entity
*/
update: {
auth: "required",
params: {
id: { type: "string" },
article: { type: "object", props: {
title: { type: "string", min: 1, optional: true },
description: { type: "string", min: 1, optional: true },
body: { type: "string", min: 1, optional: true },
tagList: { type: "array", items: "string", optional: true },
} }
},
handler(ctx) {
let newData = ctx.params.article;
newData.updatedAt = new Date();
// the 'id' is the slug
return this.Promise.resolve(ctx.params.id)
.then(slug => this.findBySlug(slug))
.then(article => {
if (!article)
return this.Promise.reject(new MoleculerClientError("Article not found", 404));
if (article.author !== ctx.meta.user._id.toString())
return this.Promise.reject(new ForbiddenError());
const update = {
"$set": newData
};
return this.adapter.updateById(article._id, update);
})
.then(doc => this.transformDocuments(ctx, { populate: ["author", "favorited", "favoritesCount"]}, doc))
.then(entity => this.transformResult(ctx, entity, ctx.meta.user))
.then(json => this.entityChanged("updated", json, ctx).then(() => json));
}
},
/**
* List articles with pagination.
*
* @actions
* @param {String} tag - Filter for 'tag'
* @param {String} author - Filter for author ID
* @param {String} favorited - Filter for favorited author
* @param {Number} limit - Pagination limit
* @param {Number} offset - Pagination offset
*
* @returns {Object} List of articles
*/
list: {
cache: {
keys: ["#token", "tag", "author", "favorited", "limit", "offset"]
},
params: {
tag: { type: "string", optional: true },
author: { type: "string", optional: true },
favorited: { type: "string", optional: true },
limit: { type: "number", optional: true, convert: true },
offset: { type: "number", optional: true, convert: true },
},
handler(ctx) {
const limit = ctx.params.limit ? Number(ctx.params.limit) : 20;
const offset = ctx.params.offset ? Number(ctx.params.offset) : 0;
let params = {
limit,
offset,
sort: ["-createdAt"],
populate: ["author", "favorited", "favoritesCount"],
query: {}
};
let countParams;
if (ctx.params.tag)
params.query.tagList = {"$in" : [ctx.params.tag]};
return this.Promise.resolve()
.then(() => {
if (ctx.params.author) {
return ctx.call("users.find", { query: { username: ctx.params.author } })
.then(users => {
if (users.length == 0)
return this.Promise.reject(new MoleculerClientError("Author not found"));
params.query.author = users[0]._id;
});
}
if (ctx.params.favorited) {
return ctx.call("users.find", { query: { username: ctx.params.favorited } })
.then(users => {
if (users.length == 0)
return this.Promise.reject(new MoleculerClientError("Author not found"));
return users[0]._id;
})
.then(user => {
return ctx.call("favorites.find", { fields: ["article"], query: { user }})
.then(list => {
params.query._id = { $in: list.map(o => o.article) };
});
});
}
})
.then(() => {
countParams = Object.assign({}, params);
// Remove pagination params
if (countParams && countParams.limit)
countParams.limit = null;
if (countParams && countParams.offset)
countParams.offset = null;
})
.then(() => this.Promise.all([
// Get rows
this.adapter.find(params),
// Get count of all rows
this.adapter.count(countParams)
])).then(res => {
return this.transformDocuments(ctx, params, res[0])
.then(docs => this.transformResult(ctx, docs, ctx.meta.user))
.then(r => {
r.articlesCount = res[1];
return r;
});
});
}
},
/**
* List articles from followed authors.
* Auth is required!
*
* @actions
* @param {Number} limit - Pagination limit
* @param {Number} offset - Pagination offset
*
* @returns {Object} List of articles
*/
feed: {
auth: "required",
cache: {
keys: ["#token", "limit", "offset"]
},
params: {
limit: { type: "number", optional: true, convert: true },
offset: { type: "number", optional: true, convert: true },
},
handler(ctx) {
const limit = ctx.params.limit ? Number(ctx.params.limit) : 20;
const offset = ctx.params.offset ? Number(ctx.params.offset) : 0;
let params = {
limit,
offset,
sort: ["-createdAt"],
populate: ["author", "favorited", "favoritesCount"],
query: {}
};
let countParams;
return this.Promise.resolve()
.then(() => {
return ctx.call("follows.find", { fields: ["follow"], query: { user: ctx.meta.user._id.toString() } })
.then(list => {
const authors = _.uniq(_.compact(_.flattenDeep(list.map(o => o.follow))));
params.query.author = {"$in" : authors};
});
})
.then(() => {
countParams = Object.assign({}, params);
// Remove pagination params
if (countParams && countParams.limit)
countParams.limit = null;
if (countParams && countParams.offset)
countParams.offset = null;
})
.then(() => this.Promise.all([
// Get rows
this.adapter.find(params),
// Get count of all rows
this.adapter.count(countParams)
])).then(res => {
return this.transformDocuments(ctx, params, res[0])
.then(docs => this.transformResult(ctx, docs, ctx.meta.user))
.then(r => {
r.articlesCount = res[1];
return r;
});
});
}
},
/**
* Get an article by slug
*
* @actions
* @param {String} id - Article slug
*
* @returns {Object} Article entity
*/
get: {
cache: {
keys: ["#token", "id"]
},
params: {
id: { type: "string" }
},
handler(ctx) {
return this.findBySlug(ctx.params.id)
.then(entity => {
if (!entity)
return this.Promise.reject(new MoleculerClientError("Article not found!", 404));
return entity;
})
.then(doc => this.transformDocuments(ctx, { populate: ["author", "favorited", "favoritesCount"] }, doc))
.then(entity => this.transformResult(ctx, entity, ctx.meta.user));
}
},
/**
* Remove an article by slug
* Auth is required!
*
* @actions
* @param {String} id - Article slug
*
* @returns {Number} Count of removed articles
*/
remove: {
auth: "required",
params: {
id: { type: "any" }
},
handler(ctx) {
return this.findBySlug(ctx.params.id)
.then(entity => {
if (!entity)
return this.Promise.reject(new MoleculerClientError("Article not found!", 404));
if (entity.author !== ctx.meta.user._id.toString())
return this.Promise.reject(new ForbiddenError());
return this.adapter.removeById(entity._id)
.then(() => ctx.call("favorites.removeByArticle", { article: entity._id }))
.then(json => this.entityChanged("removed", json, ctx).then(() => json));
});
}
},
/**
* Favorite an article
* Auth is required!
*
* @actions
* @param {String} id - Article slug
*
* @returns {Object} Updated article
*/
favorite: {
auth: "required",
params: {
slug: { type: "string" }
},
handler(ctx) {
return this.Promise.resolve(ctx.params.slug)
.then(slug => this.findBySlug(slug))
.then(article => {
if (!article)
return this.Promise.reject(new MoleculerClientError("Article not found", 404));
return ctx.call("favorites.add", { article: article._id.toString(), user: ctx.meta.user._id.toString() }).then(() => article);
})
.then(doc => this.transformDocuments(ctx, { populate: ["author", "favorited", "favoritesCount"] }, doc))
.then(entity => this.transformResult(ctx, entity, ctx.meta.user));
}
},
/**
* Unfavorite an article
* Auth is required!
*
* @actions
* @param {String} id - Article slug
*
* @returns {Object} Updated article
*/
unfavorite: {
auth: "required",
params: {
slug: { type: "string" }
},
handler(ctx) {
return this.Promise.resolve(ctx.params.slug)
.then(slug => this.findBySlug(slug))
.then(article => {
if (!article)
return this.Promise.reject(new MoleculerClientError("Article not found", 404));
return ctx.call("favorites.delete", { article: article._id.toString(), user: ctx.meta.user._id.toString() }).then(() => article);
})
.then(doc => this.transformDocuments(ctx, { populate: ["author", "favorited", "favoritesCount"] }, doc))
.then(entity => this.transformResult(ctx, entity, ctx.meta.user));
}
},
/**
* Get list of available tags
*
* @returns {Object} Tag list
*/
tags: {
cache: {
keys: []
},
handler(ctx) {
return this.Promise.resolve()
.then(() => this.adapter.find({ fields: ["tagList"], sort: ["createdAt"] }))
.then(list => {
return _.uniq(_.compact(_.flattenDeep(list.map(o => o.tagList))));
})
.then(tags => ({ tags }));
}
},
/**
* Get all comments of an article.
*
* @actions
* @param {String} slug - Article slug
*
* @returns {Object} Comment list
*
*/
comments: {
cache: {
keys: ["#token", "slug"]
},
params: {
slug: { type: "string" }
},
handler(ctx) {
return this.Promise.resolve(ctx.params.slug)
.then(slug => this.findBySlug(slug))
.then(article => {
if (!article)
return this.Promise.reject(new MoleculerClientError("Article not found", 404));
return ctx.call("comments.list", { article: article._id.toString() });
});
}
},
/**
* Add a new comment to an article.
* Auth is required!
*
* @actions
* @param {String} slug - Article slug
* @param {Object} comment - Comment fields
*
* @returns {Object} Comment entity
*/
addComment: {
auth: "required",
params: {
slug: { type: "string" },
comment: { type: "object" }
},
handler(ctx) {
return this.Promise.resolve(ctx.params.slug)
.then(slug => this.findBySlug(slug))
.then(article => {
if (!article)
return this.Promise.reject(new MoleculerClientError("Article not found", 404));
return ctx.call("comments.create", { article: article._id.toString(), comment: ctx.params.comment });
});
}
},
/**
* Update a comment.
* Auth is required!
*
* @actions
* @param {String} slug - Article slug
* @param {String} commentID - Comment ID
* @param {Object} comment - Comment fields
*
* @returns {Object} Comment entity
*/
updateComment: {
auth: "required",
params: {
slug: { type: "string" },
commentID: { type: "string" },
comment: { type: "object" }
},
handler(ctx) {
return this.Promise.resolve(ctx.params.slug)
.then(slug => this.findBySlug(slug))
.then(article => {
if (!article)
return this.Promise.reject(new MoleculerClientError("Article not found", 404));
return ctx.call("comments.update", { id: ctx.params.commentID, comment: ctx.params.comment });
});
}
},
/**
* Remove a comment.
* Auth is required!
*
* @actions
* @param {String} slug - Article slug
* @param {String} commentID - Comment ID
*
* @returns {Number} Count of removed comment
*/
removeComment: {
auth: "required",
params: {
slug: { type: "string" },
commentID: { type: "string" }
},
handler(ctx) {
return this.Promise.resolve(ctx.params.slug)
.then(slug => this.findBySlug(slug))
.then(article => {
if (!article)
return this.Promise.reject(new MoleculerClientError("Article not found"));
return ctx.call("comments.remove", { id: ctx.params.commentID });
});
}
}
},
/**
* Methods
*/
methods: {
/**
* Find an article by slug
*
* @param {String} slug - Article slug
*
* @results {Object} Promise<Article
*/
findBySlug(slug) {
return this.adapter.findOne({ slug });
},
/**
* Transform the result entities to follow the RealWorld API spec
*
* @param {Context} ctx
* @param {Array} entities
* @param {Object} user - Logged in user
*/
transformResult(ctx, entities, user) {
if (Array.isArray(entities)) {
return this.Promise.map(entities, item => this.transformEntity(ctx, item, user))
.then(articles => ({ articles }));
} else {
return this.transformEntity(ctx, entities, user)
.then(article => ({ article }));
}
},
/**
* Transform a result entity to follow the RealWorld API spec
*
* @param {Context} ctx
* @param {Object} entity
* @param {Object} user - Logged in user
*/
transformEntity(ctx, entity, user) {
if (!entity) return this.Promise.resolve();
return this.Promise.resolve(entity);
}
},
events: {
"cache.clean.articles"() {
if (this.broker.cacher)
this.broker.cacher.clean(`${this.name}.*`);
},
"cache.clean.users"() {
if (this.broker.cacher)
this.broker.cacher.clean(`${this.name}.*`);
},
"cache.clean.comments"() {
if (this.broker.cacher)
this.broker.cacher.clean(`${this.name}.*`);
},
"cache.clean.follows"() {
if (this.broker.cacher)
this.broker.cacher.clean(`${this.name}.*`);
},
"cache.clean.favorites"() {
if (this.broker.cacher)
this.broker.cacher.clean(`${this.name}.*`);
}
}
};